As we walked home, enochsmiles and I kicked around a way to formalise this as a seventh-player rule, and here's what we came up with.
The Embedded Journalist option can only be used in a game with seven people; having fewer players screws with the odds too much.
GOAL: The Embedded Journalist can only win as part of a shared victory. Toward this end, the Embedded Journalist declares his allegiance with one colour at the beginning of the game by writing that colour down on a piece of paper and hiding it. If that colour wins, the Embedded Journalist shares the victory with that colour; if all terrorists are eliminated from the board, and there are no more than three empires on the board, the Embedded Journalist can force a shared victory between the remaining empires (like the "World Peace" option, but the remaining empires don't have to agree -- the Journalists control the airwaves, so they fool the other empires into believing that the world is finally at peace). If no terrorists have ever been placed on the board, the Embedded Journalist cannot force World Peace.
The Embedded Journalist's allegiance cannot change; if his chosen ally converts to terrorism, the Embedded Journalist does not convert, but he can still share in a World Peace victory. However, the Embedded Journalist can choose at the beginning of the game to ally with the terrorists. (Perhaps he's an Al-Jazeera reporter.)
The Embedded Journalist may "go on the record" and reveal his allegiance at any time if he so chooses, but he must do so publicly; in doing so, he must reveal the paper he hid at the beginning of the game. Privately, he can lie about his allegiance all he wants, but any public announcement of his allegiance is "on the record".
ABILITIES: The Embedded Journalist does not draw cards, cannot play cards on his own (with one exception), and cannot receive revenue from oil. However, he can receive cards and money from other players if he can talk them into giving or selling him these assets; he can also try to talk other players into playing cards he has acquired.
Offsetting these weaknesses, he has one important power: before a player draws, the Embedded Journalist can look at the next two cards, and if he chooses, he may place the cards back into the deck and shuffle the deck. He can thus extort money out of the player, either threatening to shuffle back in useful cards or offering to reshuffle a bad draw. He can only use this power once per draw; if he reshuffles before the player draws, he may not look at the next two cards (unless he manages to see them in the player's hand).
The Embedded Journalist may also circle the table and snoop over other people's shoulders, though other players can hide their cards and secret messages to the best of their ability. Be careful where you leave your secret plans and sensitive intelligence!
If the Embedded Journalist comes into possession of an Intelligence Leak card, he may play it during any player's turn. Of course, he may choose to share the secret messages he receives with any other player, or he may keep them to himself.
The Embedded Journalist may not speak or write down the name of any card in the game. Doing so is considered a violation of broadcast standards and the Journalist must pay $5 million in fines to the World Bank. If he cannot afford this, he must forfeit his next two turns of lookahead (e.g., if it is player 1's turn and the Embedded Journalist violates broadcast standards, he may not look ahead on either player 2's turn or player 3's turn).
We haven't playtested these rules yet, and I don't know if we'll get a chance to do so before we leave Belgium, but I see a new addition to our board game collection in the near future....